A glass plate for automobile windows integrally includes a polyolefin molding that is placed between the glass plate and an automobile body, seals between the glass plate and the automobile body, and, if necessary, has a decorative function or the like. Although the adhesion between an inorganic substrate such as a glass plate and a polyolefin molding is required, unmodified polyolefin is a chemically inactive material with extremely poor adhesion because it does not include a polar group in its molecule.
Patent Literature 1 suggests a method for adhering a polyolefin elastomer and a glass substrate using a chlorinated polyolefin and a silane coupling agent as adhesive components (Patent Literature 1). However, in this method, the adhesion laminate of the thermoplastic elastomer and the glass substrate contains halogen, and environmental problems that occur during incineration are not completely solved.
Patent Literature 2 suggests an adhesive capable of adhering a polyolefin elastomer and a glass substrate without containing a halogen by the combined use of a maleic-anhydride-modified polyolefin, and a silane coupling agent containing an epoxy group or amino group. However, the addition of the silane coupling agent beforehand deteriorates storage stability, and thus, the silane coupling agent must be separately added during the application of the adhesive. Equipment such as a stirrer is also required for attaining sufficient homogeneity, which requires complicated steps.
Further, although Patent Literature 3 suggests a method in which a maleic-anhydride-modified polyolefin is used as an adhesive without separately adding a silane coupling agent, etc., the adhesion strength of the adhesive is insufficient.